Unpalatable Scratch n'Sniff

In response to a late meme that some grocers were electing to phase out 'sell by' or expiry dates on certain foods, I propose a consumers' tool to determine the likelihood one would be upset by the product were it purchased and found to be of doubtful or questionable quality.

Nothing real technical, like artificial chemical "aging" that starts smelling like fresh sauerkraut, say, but starts to smell like bitter fennel in a year or so. I'm suggesting a scratch pad that smells like bitter fennel, to remind a consumer what they might be getting if the product is old. When he opens the product later and smells the "bad" product smell, then there's an option to eat it anyway or chuck it out.